The invention relates to a screw, which can quickly be put into a tapped hole and tightened therein.
The known screws, customary to the trade, have to be screwed into the tapped hole from the beginning of the thread, which demands much time. In addition, if the tapped holes are accessible in a difficult way, these screws can be inserted into tapped holes only with difficulty.
The object of the invention is to develop a screw, the screwed shank of which easily engages its external thread with the internal thread of the tapped hole, when the screw enters the tapped hole, and which then has only to be tightened.
This object is achievd according to the invention by the division of the screwed shank into two halves by a slot, which runs centrally in longitudinal direction, and by the provision of two chamfers, which run vertically to the slot, on both long sides of the screwed shank.
To ensure the strength of the screw, it is advantageous when the chamfers, which are provided on the long sides of the screwed shank, be arranged at an acute angle to each other.
To simplify the insertion of the screw into the tapped hole, the front part of the screwed shank is provided with a conical taper.
Furthermore, it is advantageous when the two halves of the screwed shank are spring-loaded. In such an embodiment, the two halves of the screwed shank can be arranged so as to spread apart, whereby the clamping effect of the two halves of the screwed shank, engaged into the internal thread of the tapped hole, is improved considerably.
Due to this new form of the screw, the screwed shank can be inserted into the tapped hole without being obstructed by the thread parts on the two long sides of the slot and the two halves of the screwed shank move at first to the middle of the shank and then engage their external thread into the internal thread of the tapped hole.